The present invention relates to an airbag module comprising at least two housing parts.
Airbag modules, in particular driver side airbag modules, typically comprise two housing parts for receiving the airbag. One housing part is the actual airbag housing, which is secured to for instance a steering wheel of a motor vehicle. The second housing part typically is an airbag cover, which covers the airbag module to the outside, i.e. towards the vehicle interior. For the purpose of easy assembly, these two housing parts are preferably latched together during the assembly.
It is problematic, however, that during the activation of the airbag module, extremely high forces operate on the airbag cover. Despite these high forces it must be ensured that the airbag cover is not detached from the airbag housing. The airbag cover should open only at the set breaking points to enable an ejection of the airbag. The known catch connections comprising a catch nose and a corresponding catch opening, in which the catch nose engages, have often been unsatisfactory in this respect, since during the deployment of the airbag the catch noses were torn off due to the high forces that arise during deployment of the airbag.
There is provided in accordance with the present invention an airbag module comprising at least two housing parts securely connected to each other by a mechanical catch connection. At least one catch hook is arranged on the first housing part and at least one tab with a corresponding catch opening that is arranged in the second housing part. During the latching together of the two housing parts, the catch hook engages the corresponding catch opening. To achieve a secure connection of catch hook and catch opening, at least one ramp is arranged on the first housing part, opposite the catch hook, which ramp rises in the insertion direction of the second housing. This means that the ramp rises in the direction in which the second housing part is moved toward the first housing part during assembly. This has the result that, during the assembly of the first housing part with the second housing part, the tab of the second housing part comes into contact with the ramp during the latching and is deflected by the ramp in the direction of the catch hook. The deflection of the tab results in the catch opening being deflected or pushed in the direction of the catch hook. The catch hook fully engages the catch opening and in there is the greatest possible contact surface between catch hook and catch opening. Because of the ramp, during the latching a maximal contact surface is always achieved between catch opening and catch hook, it can be ensured that during the deployment of the airbag the ensuing forces are distributed on as large a surface as possible. In this way stressing the catch hook can be reduced, so that a malfunction or tearing off of the catch hook can be avoided. In addition, the catch hook need not be unnecessarily long, i.e. jutting out transverse to the insertion direction, so that the deflection of the catch hook required during the insertion of the tab can be kept to a minimum.